Answer:
D. 4Fe + 302 --> 2Fe2O3
Step-by-step explanation:
The equation that bests supports the law of conservation of mass is the choice D;
4Fe + 3O₂ → 2Fe₂O₃
Based on the law of conservation of mass, the number of atoms on both sides of the expression must be the same. Only the fourth choice proves this law;
4Fe + 3O₂ → 2Fe₂O₃
Number of atoms
Elements Left hand side Right hand side
Fe 4 4
O 6 6
We can see that both side of the expression have the same number of atoms and the equation is balanced.